Give profile menus more straightforward hide/disable/delete/default interactions

Summary:
Ref T10054.

  - Just let users delete non-builtin items.
  - Let users choose a default item explicitly.
  - Do a better job of cleaning up items which no longer exist or belong to uninstalled applications.

(NOTE) This has one user-facing change: workboards are no longer the default on projects with workboards. I think this is probably OK since we're giving users a ton of new toys at the same time, but I'll write some docs at least.

Test Plan:
  - Deleted custom items.
  - Disabled/enabled builtin items.
  - Made various things defaults.
  - Uninstalled Maniphest, saw Workboards tab disappear entirely.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10054

Differential Revision: https://secure.phabricator.com/D15089

src/applications/project/controller/PhabricatorProjectViewController.php

@@ -17,21 +17,14 @@ final class PhabricatorProjectViewController
     }
     $project = $this->getProject();
 
-    $columns = id(new PhabricatorProjectColumnQuery())
-      ->setViewer($viewer)
-      ->withProjectPHIDs(array($project->getPHID()))
-      ->execute();
-    if ($columns) {
-      $controller = 'board';
-    } else {
-      $controller = 'profile';
-    }
+    $engine = $this->getProfilePanelEngine();
+    $default = $engine->getDefaultPanel();
 
-    switch ($controller) {
-      case 'board':
+    switch ($default->getBuiltinKey()) {
+      case PhabricatorProject::PANEL_WORKBOARD:
         $controller_object = new PhabricatorProjectBoardViewController();
         break;
-      case 'profile':
+      case PhabricatorProject::PANEL_PROFILE:
       default:
         $controller_object = new PhabricatorProjectProfileController();
         break;